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Journal of Iron and Steel Research(International) 2024年第4期31卷 882-893页

作者： Shun-hu Zhang Yan Li Li-zhi Che Wen-hao tian Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The prediction accuracy of existing models of the rolling force of a thick plate is always very low.To address this problem,a high-precision genetic algorithm-backpropagation network(GA-BP)model of deformation resistance was built,and its integration with the traditional fitted model was further established.Then,a novel rolling force model was obtained by embedding the integration model of deformation resistance in the original model of rolling force.According to this research idea,the industrial data are normalized at first.On this basis,the interactions among the process parameters were disclosed through the variance analysis,and then described by various virtual factors.These factors are set as part of input parameters.Then,the optimal structure of the GA-BP model of deformation resistance was determined and an integration model of deformation resistance was built.Finally,a novel rolling force model is obtained by substituting the traditional fitted deformation resistance into the Sims model with the integration model of the deformation resistance.The results proves that the introduction of virtual factors can increase the hit rate of±5%from 75.8%to 78%and can reduce the root mean square error from 4.72%to 4.48%.Besides,it is found that the mean relative error of the traditional fitted deformation resistance is 0.142,while that of the modified deformation resistance is only 0.03.In addition,the mean relative error in the original rolling force model is 0.145,while that of the present model is only 0.03.

关键词： Integration model-Deformation resistance Variance analysis Virtual factor Genetic algorithm-backpropagation network model

Learnware:small models do big

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Science China(Information Sciences) 2024年第1期67卷 39-50页

作者： zhi-Hua ZHOU zhi-hao TAN National Key Laboratory for Novel Software Technology Nanjing University

There are complaints about current machine learning techniques such as the requirement of a huge amount of training data and proficient training skills,the difficulty of continual learning,the risk of catastrophic forgetting,and the leaking of data privacy/proprietary.Most research efforts have been focusing on one of those concerned issues separately,paying less attention to the fact that most issues are entangled in practice.The prevailing big model paradigm,which has achieved impressive results in natural language processing and computer vision applications,has not yet addressed those issues,whereas becoming a serious source of carbon emissions.This article offers an overview of the learnware paradigm,which attempts to enable users not to need to build machine learning models from scratch,with the hope of reusing small models to do things even beyond their original purposes,where the key ingredient is the specification which enables a trained model to be adequately identified to reuse according to the requirement of future users who know nothing about the model in advance.

关键词： artificial intelligence machine learning learnware

Bioengineered skin organoids:from development to applications

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Military Medical Research 2024年第3期11卷 449-466页

作者： Zi-Xuan Hong Shun-tian Zhu hao Li Jing-zhi Luo Yu Yang Yang An Xi Wang Kai Wang Department of Physiology and Pathophysiology School of Basic Medical SciencesState Key Laboratory of Vascular Homeostasis and RemodelingPeking UniversityBeijing 100191China Department of Hepatopancreatobiliary Surgery the Third Affiliated Hospital of Soochow UniversityChangzhou 213000JiangsuChina Department of Plastic Surgery Peking University Third HospitalBeijing 100191China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China State Key Laboratory of Cardiovascular Disease Fuwai HospitalBeijing 100037China Beijing Key Laboratory of Metabolic Disorder Related Cardiovascular Disease Capital Medical UniversityBeijing 100050China

Signifcant advancements have been made in recent years in the development of highly sophisticated skin organoids.Serving as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex structures and are increasingly recognized as efective alternatives to traditional culture models and human skin due to their ability to overcome the limitations of two-dimensional(2D)systems and ethical concerns.The inherent plasticity of skin organoids allows for their construction into physiological and pathological models,enabling the study of skin development and dynamic changes.This review provides an overview of the pivotal work in the progression from 3D layered epidermis to cyst-like skin organoids with appendages.Furthermore,it highlights the latest advancements in organoid construction facilitated by state-of-the-art engineering techniques,such as 3D printing and microfuidic devices.The review also summarizes and discusses the diverse applications of skin organoids in developmental biology,disease modelling,regenerative medicine,and personalized medicine,while considering their prospects and limitations.

关键词： Skin organoid Organoid generation Skin appendage Tissue engineering Disease modelling Regenerative medicine

P-symmetric Subharmonic Solutions for Nonlinear Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1388-1408页

作者： Duan zhi ZHANG zhi hao Zhao School of Mathematical Sciences Nankai UniversityTianjin 300071P.R.China

In this paper,we prove that for each positive k≡1 mod m there exists a P-symmetric kmτ-periodic solution xk for asymptotically linear mτ-periodic Hamiltonian systems,which are nonautonomous and endowed with a P-symmetry.If the P-symmetric Hamiltonian function is semi-positive,one can prove,under a new iteration inequality of the Maslov-type P-index,that xk_(1) and xk_(2) are geometrically distinct for k_(1)/k_(2)≥(2n+1)m+1;and xk_(1),xk_(2) are geometrically distinct for k_(1)/k_(2)≥m+1 provided xk_(1) is non-degenerate.

关键词： P-symmetric subharmonic Hamiltonian systems Maslov-type index theory iteration inequality asymptotically linear

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： tian-hao Yang Tong Wu Qiang Fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Classifying Chinese Medicine Constitution Using Multimodal Deep-Learning Model

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Chinese Journal of Integrative Medicine 2024年第2期30卷 163-170页

作者： GU tian-yu YAN Zhuang-zhi JIANG Jie-hui School of Communication&Information Engineering Shanghai UniversityShanghai(200444)China School of Life Science Shanghai UniversityShanghai(200444)China

Objective:To develop a multimodal deep-learning model for classifying Chinese medicine constitution,i.e.,the balanced and unbalanced constitutions,based on inspection of tongue and face images,pulse waves from palpation,and health information from a total of 540 subjects.Methods:This study data consisted of tongue and face images,pulse waves obtained by palpation,and health information,including personal information,life habits,medical history,and current symptoms,from 540 subjects(202 males and 338 females).Convolutional neural networks,recurrent neural networks,and fully connected neural networks were used to extract deep features from the data.Feature fusion and decision fusion models were constructed for the multimodal data.Results:The optimal models for tongue and face images,pulse waves and health information were ResNet18,Gate Recurrent Unit,and entity embedding,respectively.Feature fusion was superior to decision fusion.The multimodal analysis revealed that multimodal data compensated for the loss of information from a single mode,resulting in improved classification performance.Conclusions:Multimodal data fusion can supplement single model information and improve classification performance.Our research underscores the effectiveness of multimodal deep learning technology to identify body constitution for modernizing and improving the intelligent application of Chinese medicine.

关键词： Chinese medicine constitution classification multimodal deep learning tongue image face image pulsewave health information

Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector

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Nuclear Science and Techniques 2024年第2期35卷 123-130页

作者： Da-Wei Si Yan Zhou Sheng Xiao zhi Qin Dong Guo Yu-hao Qin Yi-Jie Wang Bo-Yuan Zhang Bai-Ting tian zhi-Gang Xiao Department of Physics Tsinghua UniversityBeijing 100084China

The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.

关键词： Bremsstrahlungγ-rays Čerenkov Geant4 Energy resolution Direction reconstruction Hough transform

Interplay between mesenchymal stem cells and macrophages:Promoting bone tissue repair

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World Journal of Stem Cells 2024年第4期16卷 375-388页

作者： Fei-Fan Zhang Yang hao Kuai-Xiang Zhang Jiang-Jia Yang zhi-Qiang Zhao Hong-Jian Liu Ji-tian Li Molecular Biology Lab Henan Luoyang Orthopedic Hospital(Henan Provincial Orthopedic Hospital)Zhengzhou 450000Henan ProvinceChina Graduate School Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Graduate School Henan University of Chinese MedicineZhengzhou 450046Henan ProvinceChina Department of Orthopaedics The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

The repair of bone tissue damage is a complex process that is well-orchestrated in time and space,a focus and difficulty in orthopedic treatment.In recent years,the success of mesenchymal stem cells(MSCs)-mediated bone repair in clinical trials of large-area bone defects and bone necrosis has made it a candidate in bone tissue repair engineering and regenerative medicine.MSCs are closely related to macrophages.On one hand,MSCs regulate the immune regulatory function by influencing macrophages proliferation,infiltration,and phenotype polarization,while also affecting the osteoclasts differentiation of macrophages.On the other hand,macrophages activate MSCs and mediate the multilineage differentiation of MSCs by regulating the immune microenvironment.The cross-talk between MSCs and macrophages plays a crucial role in regulating the immune system and in promoting tissue regeneration.Making full use of the relationship between MSCs and macrophages will enhance the efficacy of MSCs therapy in bone tissue repair,and will also provide a reference for further application of MSCs in other diseases.

关键词： Bone tissue damage Inflammation Macrophages Mesenchymal stem cells Tissue regeneration

Effect of Fe Addition on Dehydrogenation Performance of Methylcyclohexance over Pt/Al_(2)O_(3)

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 12-18页

作者： Tong Fengya tian hao Wang hao Miao Changxi Song Lei Shanghai Research Institute of Petrochemical Technology SINOPEC Shanghai201208

Catalysts with varying Fe contents were prepared using a sequential impregnation method to investigate the effects of Fe addition on the physicochemical properties of Pt/Al_(2)O_(3) and their performance in methylcyclohexane(MCH)dehydrogenation.The results demonstrated that the addition of Fe to Pt/Al_(2)O_(3) enhanced the electron density of Pt and improved catalytic activity,while exhibiting negligible influence on the catalytic selectivity for toluene.When the Fe content was 0.057%,the catalyst exhibited the highest MCH consumption rate,which was approximately two times higher than that of the catalyst without Fe.Additionally,the incorporation of Fe inhibited the formation of coke and reduced the quantity of coke deposits on the catalyst,thereby improving its catalytic durability.Overall,Fe shows promise as a prospective secondary element for Pt/Al_(2)O_(3) to enhance the MCH dehydrogenation performance.

关键词： methylcyclohexane dehydrogenation hydrogen storage deactivation Fe addition

Along-track Calibration of the Zhurong Rover Magnetometer

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Science China Earth Sciences 2024年第2期67卷 552-565页

作者： hao LUO Aimin DU Yasong GE Ying ZHANG Haiying LI Lin tian Kuixiang ZHANG Shuquan SUN Lin Zhao zhi LI Xiao FENG CAS Engineering Laboratory for Deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth Science University of Chinese Academy of SciencesBeijing100049China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China

As part of the Chinese tianwen-1 mission,the Zhurong Rover began its scientific investigation in the southern Utopia Planitia after its successful landing in 15 May,2021.The Zhurong Rover magnetometer(RoMAG),one of the six payloads onboard the rover,includes two identical high-sensitivity triaxial fluxgate magnetometers and can implement mobile magnetic measurements on the surface of Mars.Although a rover magnetic compensation procedure was conducted to remove the magnetic interferences pre-launch,due to the different state of the payloads and electric power system such as the solar panel,an along-track calibration of the magnetometer is necessary to obtain a more accurate Martian magnetic field.Two methods,mast yaw rotations and Rover yaw rotations were utilized separately to determine the Martian horizontal magnetic components.Results show that the Martian horizontal magnetic components determined by the two methods are in good agreement,with the root mean square deviation less than 2.0 nT.The vertical component was also constrained through the pitch movements of the mast by assuming the interferences field distributes like a dipole field.A linear correlation between magnetic field measurements and the solar array currents was derived to calibrate the body field during the regular exploration.We conclude that more accurate measurements could be made when applying the calibration results in the magnetic survey on the surface of Mars.

关键词： The Zhurong Rover Magnetometer Along-track calibration Remnant magnetization